Submitted to: European Journal of Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/24/2007
Publication Date: 9/10/2007
Citation: Muehlbauer, F.J., Chen, W. 2007. Resistance to ascochyta blights of cool season food legumes.. European Journal of Plant Pathology.
Interpretive Summary: Cool season food legumes (pea, chickpea, lentil, and faba bean) are affected by a number of foliar and root diseases that cause wide spread damage and in severe cases cause complete crop loss. Foremost and by far the most prominent among the foliar diseases is Ascochyta blight. Although the diseases of these crops are collectively referred to as Ascochyta blight due to similar blight symptoms, the pathogen species differ for each of the crops. The Ascochyta blight complex of pea involves three pathogens, Ascochyta pisi, Mycosphaerella pinodes, and Phoma medicaginis var. pinodella (formerly Ascochyta pinodella). Resistance is the most economical means to manage Ascochyta blight in graim legumes. Significant research progress has been made in research of host resistance to Ascochyta blight. This paper reviews the recent progress and point out some of the pressing issues and limiting factors that we face in future research on host resistance to Ascochyta blight.
Technical Abstract: Ascochyta blight is the most important disease problem of the cool season food legumes (peas, lentils, chickpeas, and faba beans) and is found in nearly all production regions around the world. Despite of the same common disease name, the pathogen species differ for each of the crops. These diseases may cause serious yield loses under cool and humid conditions favorable for the diseases. Planting resistant cultivars is often the first choice and most economical means in managing the diseases. Therefore breeding for resistance to Ascochyta blight has been an important objective of many breeding programs of cool season food legumes. Systematic screening of germplasm collections at international research centers and other national research programs has identified useful resistance sources. The resistance sources have been used successfully at various degrees in breeding programs. Genetic studies have begun to reveal inheritance patterns of the resistance genes. Genetic linkage analyses and QTL mapping have identified molecular markers that could be useful in developing marker-assisted selection and gene pyramiding. In general, however, the research in developing resistance to Ascochyta blight in cool season food legume faces mainly two limitations: the unavailability of highly resistance sources and lack of a good understanding of variability of the pathogen populations. Research efforts to alleviate these limitations should be encouraged and pursued. Given that modern technologies of marker development and genomics are available now, further advances in deploying resistance to manage Ascochyta blight in this group of legume crops will depend on concerted efforts in developing accurate screening procedures with adequate knowledge of pathogen variability and identifying additional resistance sources.